I am so screwed.

I just finished my calculus test and am now facing a painful stage of defeat pain and self pity. Being capable was the only thing I had going for me and now I most definitely will have an F in math. I have become nothing. Ibdon't know what my problem is. I do the homework and I review over practice twsta and I go 'yea! Ibget this. It's not that hard. ' Then the testvis in front of me and I read. Andbi go blanks. A knawing of anciety takes over me and I find myswlf frantically trying to make senae of the jumble on the paper. When had I gotten into this mentality? Why am I so fearful? Now it's all over. Yes, most of what I type will be overdramatic. But the these feelings are cold reality to me. I have no future. I am a failure. I want to give up.why is everything in my life so unsatisfactory?
Gaaaah! I can't even scream in frustration!  So used to silencing may lf and screaming in my head. I'll probably be a mental case by 30. Dammit I hate being this pathetic. Whyyyyyyyyyyyyyyyyyy!